The present invention relates to a process and to a vacuum mold for the manufacture of a textile covered cushion, in particular a seat cushion for use inside a motor vehicle, by back foaming, in which the cover is placed on the edge of a vacuum mold and is stretched before a vacuum is applied to the cavity. The cover is sucked into position and a foamable reaction mixture is then applied to the back of the cover. After the reaction mixture has set to form the foam core the cushion is removed from the mold.
When a cover is positioned and fixed on the edge around the mold cavity by means of a stretching frame (U.S. Pat. No. 3,943,215), the cover frequently sags into the mold cavity. This may cause creases. If the cover is patterned on the visible side or if it is composed of various patterned or unpatterned sections of different colors joined together, inaccurate positioning of the cover inside the cavity may lead to irreparable damage so that the part has to be scrapped. Such an obvious fault would clearly be unacceptable to the customer.
The problem arises of providing a process and a vacuum mold by which the formation of creases in the manufacture of such a cushion can be avoided. Covers composed of patterned or unpatterned sections or different colors can be accurately and reproducibly positioned.